The present invention relates to a reset mechanism responsive to loss of torque, with applicability for resetting a device when a motor loses power.
In some types of equipment, it is desirable that an element retract if power is removed from a drive motor, without any use of additional or continuing power. Such "fail-safe mechanisms" should not increase the power requirement of the motor greatly.
Spring return mechanisms are well known for many purposes. They suffer the typical disadvantage that, as spring displacement is increased from the "reset" or power-off position to the normal operating position, the spring force increases linearly with displacement. When resetting is partially accomplished, the available spring force is relatively low.